The mystery of the dying ducks at Verulamium Lake is one step closer to a resolution.

St Albans district council believes avian botulism is what could have caused the feathered fatalities - a paralytic disease caused by ingestion of a toxin produced by the bacteria clostridium botulinum.

The toxin affects the nervous system by preventing impulse transmission to muscles. Birds are unable to use their wings and legs normally or control the third eyelid, neck muscles, and other muscles.

Birds with paralysed neck muscles cannot hold up their heads and often drown. Death can also result from water deprivation, electrolyte imbalance, respiratory failure, or predation.

Numerous duck deaths and a diminishing duck population have been reported by Verulamium Park-goers in the past few weeks.

Dog owners have also been warned of the effects after somer pooches became ill from drinking the lake water.

The council have been working with the Animal and Plant Health Agency (APHA) to determine the cause and are currently waiting on test results.

A spokesperson said: “As a precaution, the council is updating the signage placed around the lake with appropriate advice for visitors to the park.”